The prior art crown caps generally require an auxiliary tool for removing the caps therefore, rendering it very inconvenient to the user especially at picnics or in the woods where a bottle opener is not readily available. In view of this, there were designs of easy open means for crown cap of a bottle, such as U.S. Pat. Nos. 3,200,982; 3,382,997 and 2,778,520 etc. With respect to the structure, although all those designs have score lines and tongue element, yet, owing to their improper position on the cap, which is against the direction of the applied force, hence during opening, a considerable force is still required. Particularly, if the liquid in the bottle contains carbon dioxide pressure, it would be difficult to effect both perfect tight seal and easily opened closure.